docs: def run_single_with_display(wf, display):
      """Adds a display to the single runner. Everything still runs in a single
      thread. Every time a job is pulled by the worker, a message goes to the
      display routine; when the job is finished the result is sent to the display
      routine."""
      S = Scheduler(error_handler=display.error_handler)
      W = Queue() \
          >> branch(log_job_start.to(sink_map(display))) \
          >> worker \
          >> branch(sink_map(display))
  
      return S.run(W, get_workflow(wf))